An oscilloscope is an instrument used for the measurement, analysis and display operations. Cathode ray oscilloscope makes use of cathode ray tube, a vacuum tube device. A cathode ray tube consists of an electron gun, two pairs of deflection plates, and a phosphor screen. The components of electron gun are heater, oxide coated cathode, anodes and a control grid. Heater heats up cathode and cathode emit electrons. Anode serves the purpose of fine focusing and acceleration of electrons towards screen. A dual beam oscilloscope has two different electron guns producing two separate beams. It also consists of two separate vertical channels and one horizontal time-base unit. Study of two separate waveforms simultaneously is the main purpose of dual beam oscilloscopes. But they are expensive. In dual-trace oscilloscopes, only one electron gun and one set of vertical and horizontal deflection plates exist. But dual trace oscilloscopes are capable of performing all the operations performed by a dual beam oscilloscope. An appropriate switching operation is helping to achieve this multifunction.